具有多列的oracle汇总函数

Question

我有一个简单的查询:

WITH data(val1, val2, val3) AS
     ( SELECT 'a' ,'a-details' ,'1' FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot
from data
group by rollup(val1, val2);

我得到一个输出:

VAL1                             VAL2                                    TOT
-------------------------------- -------------------------------- ----------
a                                a-details                                 1 
a                                                                          1 
b                                b-details                                 2 
b                                                                          2 
c                                c-details                                 3 
c                                                                          3 
Total Result                                                               6 

但我需要一个输出,如:

VAL1                             VAL2                                    TOT
-------------------------------- -------------------------------- ----------
a                                a-details                                 1 
b                                b-details                                 2 
c                                c-details                                 3 
Total Result                                                               6 

提前致谢.

Answer 1

我发现使用GROUPING SET子句指定我需要的确切集更容易:

WITH data(val1, val2, val3) AS
     ( SELECT 'a' ,'a-details' ,'1' FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot
from data
group by grouping sets ((val1, val2),());

我怀疑它更有效率,因为它直接指定要计算的水平.

http://sqlfiddle.com/#!4/8301d/3

CUBE和ROLLUP用于自动生成大量聚合级别(例如,维度层次结构中的每个级别),如果您想从大型CUBE生成中消除一小部分级别,则可能存在使用GROUPING ID的情况设置,但GROUPING SET精确设计用于指定特定的聚合级别.

Answer 2

GROUPING_ID表达式

您可以使用GROUPING_ID表达式来过滤所需的小计级别:

WITH data AS
     ( SELECT 'a' AS val1 ,'a-details' AS val2 , '1' AS val3 FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot
from data
group by ROLLUP(val1, val2)
HAVING GROUPING_ID(val1, val2) IN (0, 3);

输出:

NVL(VAL1,'TOTALRESULT') VAL2             TOT
----------------------- --------- ----------
a                       a-details          1 
b                       b-details          2 
c                       c-details          3 
Total Result                               6 

GROUPING_ID 对于没有小计的行返回0,对于第一级返回1,依此类推,我们可以查看它返回的值:

WITH data AS
     ( SELECT 'a' AS val1 ,'a-details' AS val2 , '1' AS val3 FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot,
     GROUPING_ID(val1, val2) AS grp_id
from data
group by ROLLUP(val1, val2);

NVL(VAL1,'TOTALRESULT') VAL2             TOT     GRP_ID
----------------------- --------- ---------- ----------
a                       a-details          1          0 
a                                          1          1 
b                       b-details          2          0 
b                                          2          1 
c                       c-details          3          0 
c                                          3          1 
Total Result                               6          3 

检查SQLFiddle

关于Rollup和相关主题的更多信息:Tim Hall关于Rollup和Cube

(编辑)

GROUPING功能

关于评论.你可以使用这个GROUPING功能:

GROUPING - 接受单个列作为参数,如果列包含由a ROLLUP或CUBE操作作为小计的一部分生成的空值,则返回"1 ";对于任何其他值(包括存储的空值),包含"0".

返回值的示例:

WITH data AS
     ( SELECT 'a' AS val1 ,'a-details' AS val2 , '1' AS val3 FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot,
     grouping(val1),
     grouping(val2)
from data
group by ROLLUP(val1, val2);

输出:

NVL(VAL1,'TOTALRESULT') VAL2             TOT GROUPING(VAL1) GROUPING(VAL2)
----------------------- --------- ---------- -------------- --------------
a                       a-details          1              0              0 
a                                          1              0              1 
b                       b-details          2              0              0 
b                                          2              0              1 
c                       c-details          3              0              0 
c                                          3              0              1 
Total Result                               6              1              1

所以你的查询应该是这样的:

WITH data AS
     ( SELECT 'a' AS val1 ,'a-details' AS val2 , '1' AS val3 FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot
from data
group by ROLLUP(val1, val2)
HAVING GROUPING(val1) = 1
   OR (GROUPING(val1) + GROUPING(val2) = 0);

输出:

NVL(VAL1,'TOTALRESULT') VAL2             TOT
----------------------- --------- ----------
a                       a-details          1 
b                       b-details          2 
c                       c-details          3 
Total Result                               6

在这里使用GROUPINGAskTom 的功能的想法.